As this is still an issue, I don't really think this is too much of a thread necro... but, we were at Stern and talked to one of the guys about our issues with the ball getting stuck under the hammer. They knew what we were talking about and went and got a new "subway" for us. Said the original one was bent where the ball comes down.

After getting the new one and the old one side by side you could see the issue. As I was an idiot and didn't take any pictures of the replacement, here's a couple of pictures of the original one; with the bends and one after I manually bent them back to where they looked like the new one. The balls where getting stuck on the right side of the ramp (when it's installed, left as you're looking at it in the pictures). The ball would sit where the bottom was bent down. The new ramp fixed that issue, but if you're having this issue... check the bottom of the subway where the balls drop down in to it.

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